MaxxForce DT Cylinder Head Installation

September 3, 2018

Installing the cylinder head on an International MaxxForce DT diesel engine is intimidating for the novice but as I always say follow the instructions in the manual to the letter and you will never go wrong. The video specifically shows how to torque down the head bolts after the threads are coated with a light layer of engine oil. The first 2 steps are a circular pattern and the last 2 steps have a different pattern running straight across left to right.

The replacement of the head bolts is essential since bolts under extreme stress will stretch. It’s very good insurance to take this step seriously to avoid failure down the road. Could you get away with reusing the head bolts? It’s a gamble in my opinion. There is so much work involved to install the cylinder head. Any shortcuts are not recommended. Follow the manual….. period. Take your time as well carrying out these steps involving torquing fasteners and reassembling the engine.

Come backs is something I don’t want to see and make sure the techs get enough time to do the job correctly. The running checks and road test at the end of any job is mandatory. A service call takes time out of our regular routine and most times during irregular hours. Some times it can’t be helped due to bad luck or a faulty part. Once the head is torqued down and double checked (always) the rockers, injectors, electrical harness and high pressure manifold is installed.

All of these components are resealed with new parts provided by the in-frame kit. The high pressure manifold must seal to prevent leakage of high pressure oil from the HPOP (high pressure oil pump). Pressures will reach up to 4900 psi to operate the injectors at full load and full throttle. The high pressure manifold also houses the engine brake system which hydraulically actuates pistons to open the exhaust valves when the operator turns on the engine brake switch.

The high pressure oil does create a problem when it drops off effecting engine operation. Usually you can not do a quick fix on the road unless an external high pressure oil line has failed. Most times it’s internal under the valve cover which takes some determination to remove. So there are lots of things going on with the cylinder head and it’s related components. Our shop crew knows these engines now and there are lots of the same issues happening. Another five years minimum before we start thinking about getting rid of these engines so the more comfortable we are working on them the better. Stay tuned.